Spabk-plug



- 1. BURGKEHT.

SPARK PLUG. APPLICATION FILED SEPT. l-5 19H- v Patented De@.16,1919;

UNITED STATES PATENT oEEICE.

JOSEPH BURGERT, OF LAKEWOOD, OHIO, ASSIGNOR OF ONE-THIRD TO MAX P.GOODMAN AND ONE-THIRD TO GEORGE JANOWITZ, 'BOTH OF CLEVELAND,

OHIO.

SPARK-PLUG.

Specication of Letters Patent. Patented Dec. 16, 1919.

Application filed September 15, 1917. Serial No. 191,523.

T 0 all lwhom t may concern:

Be it known that-I, JOSEPH BURGERT, acitizen of the United States,residing at Lakewood, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Spark-Plugs, of whichvthe following is a full, clear, and exact description, reference beinghad to the accompanying drawings.

This invention relates to spark plugs for use as the ignition terminalfor internal combustion engines. The object is to provide, in a simpleform, a plug which shall automatically drain liquid deposited within theplug or on the electrodes and thus lmaintain the contact points cleanand avoid the troublesome carbon deposit on the electrodes, whichresults with many plugs. l

In accomplishing the above end, I provide the central electrode of theplug in a form which presents a small cup for catching liquid gasoleneor oil running down from the interior of the plug, the exterior of thiscup coacting with the other electrode while the interior is drained atone or more points comparatively distant from such other electrode. `Theside' electrode carried by the wall of the plug is formed into hookshape,

the inner extremity of which stands adja-,

cent to the outer edge of the cup of the central electrode. 'Thesparking therefore, takes place from the high points of both the cup andthe hook, and liquid on the hook or the outside of the cup, forming in adrop at the lowest point, is immaterial.

By the above means I am able to preserve the parts of the two electrodeswhere the fspark is formed free from liquid and the resultant carbondeposit. My invention is hereinafter more fully explained and .itsessential characteristics are summarized in the claims.

In the drawing, Figure 1 is a side elevation of my improved spark plug;Fig. 21s a vertical central section of the same; Fig. 3 is a bottomplanof the plug; Fig. 4f is an enlarged cross section through the twoelectrodes, on the line ot' Fig. 2 looking downwardly.

In the drawings, 10 indicates the outer or metal sleeve member of theplug. This is shown as having an externally threaded ortion 11 adaptedto screw into the engine ead, an external annular shoulder 1:2 to

limit the movement, and an angular portion 13 for the application of awrench. The side electrode 20 is carried by the lower end of thethreaded sleeve 10. This electrode is made in the hooked form shown, itshooked portion lying in a radial plane and pointing toward the head ofthe plug.

30 indicates the central electrode which is carried axially within asuitable insulating sleeve 40. This sleeve is shown as having an annularboss l which rests on an internal shoulder of the metal sleeve 10. Ametal clamping bushing 50 is threaded into the upper portion of thesleeve 10 and bears downwardly against the upper shoulder of the bossLi1. Suitable metallic rings may be provided at the upper and lower`shoulders ofthe boss 41 to make a gas-tight connection between theinsulation and metallic sleeve.

The lower end of the rod 30 continues below the insulating sleeve in astem 31, which may be enlarged and abut the lower end of the insulation.This stem carries concentric with it a peculiar cup-shaped head 32. Thishead has a rounded end, and a conical Wall surrounding the stem, andleaving an annular groove 33 withinthe cup and about the stem. One ormore draining openings 34 are formed through the wall of the cup atpoints relatively distant from the end 21 of the side electrode.

The conical form of the cup causes it to present a sharp upper edgewhich, at one point, Stands adjacent to the end of the re-curved portion21 of the side electrode. The sparking, therefore, takes place betweenthese points. As these points are the highest parts ofthe side hook andof the central cup, they are kept free from the liquid which may bedeposited thereon. Any liquid deposited on the stem or the insulatingsupport drains into the cup, and from thence drains through the openings34.- away from the point 2l.

The head '32 may be formed on'the electrode rod 30 in any desiredmanner. It is very convenient to make it an integral portion of the rodand to provide the enlargement 31 of the rod at 31 just above the cup'.lVith such construction the rod 30 is inserted into the insulatingsleeve from below. The connection at-.the upper end of the centralelectrode rod may take any form desired. I have shown a nut 60 screwingonto thevrod and bearing against the upper end of the insulating sleeve40. Above this nut is a clamping thumb nut 61.

It will be understood from the description that my spark plug is simplein construction and may be cheaply made. Due to the peculiar formationof the cup on the central electrode, I maintain the sparking partsconstantly in clean condition for most eflicient sparking.

Having-.thus described my invention, what I claim is:y

lM In a spark plug, the combination of a metallic sleeve, an electrodecarried thereby and projecting wardly, an insulating plug within thesleeve, a rod occupying the sleeve carrying an electrode at its lowerend, said last mentioned electrode having an upwardly facing cup-shapedhead, the edge of which is adjacent to the end of the electrode irst,mentioned, there being a groove within the cup-shaped wall below theinsulating plug and a draining opening through the side wall of the cup,which opening is relatively distant from the electrode first mentioned.

2. In a spark plug, the combination of a metallic sleeve, an electrodecarried thereby, an insulating plug within the metallic sleeve9 acentral rod within the insulating plug, an extension on the rod belowthe insulating lplug terminatingin an integral upwardly facing cup, saidcup leaving an annular groove betweenit and the body of the extension,draining openings through the wall of the cup on opposite sides of theextension, the electrode first mentioned terminating adjacent to thewall of the cup at a point between the draining openings.

3. In a spark plug, the combination of a metallic sleeve adapted toscrew into the engine, an electrode carried thereby in the form of ahook with an upwardly extending inner portion, an insulating sleevecarried by the metallic sleeve, and an electrode rod mounted in theinsulating sleeve and having a head at its lower end, said head beingapproximately in the form of an inverted mushroom, the edge of which atone place stands adjacent to the point of the hook, said head having acavity 'behind its wall and there being a draining opening through thewall at a place relatively distant from the point of the otherelectrode.

In testimony whereof, I hereunto ax my signature.

JOSEPH BJURGERCTe

